Universal coupling

ABSTRACT

A spherical coupling that utilizes a ball structure attached to one part to be coupled, and a socket structure that attaches to the other part to be coupled. One embodiment of the improvement structure disclosed utilizes a front opening housing having a stationary cam therein and a rotating outer shell that engages the ball and causes it to seat in the socket upon rotation of the outer shell. Upon completion of the engagement, the outer shell is locked in a holding position.

United States Patent [191 Bernhardt et a1.

[ 51 Aug. 27, 1974 UNIVERSAL COUPLING [76] Inventors: Brian M. Bernhardt, 1226 Bardfield St, Dallas, Tex. 75041; Edward A. Genzel, 1317 Larry Dr., Dallas, Tex. 7504] [22] Filed: Aug. 8, 1972 211 App]. No.: 278,756

[52] US. Cl. 280/5111 [51] Int. Cl B60d 1/06 [58] Field of Search 280/511, 512, 513

[56] References Cited UNITED STATES PATENTS 2,179,432 11/1939 Schroeder et a1 280/511 R 2,793,881 5/1957 Albritton 280/512 R 2,797,406 6/1957 Tanis et a1. 280/511 X 2,799,921 6/1957 Knop et a1. 280/51 1 X 3,184,254 5/1965 Seeley 280/513 R 3,374,268 3/1968 Groves 280/512 R Primary Examiner-*Leo Friaglia Assistant Examiner-Randall A. Schrecengost ABSTRACT A spherical coupling that utilizes a ball structure attached to one part to be coupled, and a socket structure that attaches to the other part to be coupled. One embodiment of the improvement structure disclosed utilizes a front opening housing having a stationary cam therein and a rotating outer shell that engages the ball and causes it to seat in the socket upon rotation of the outer shell. Upon completion of the engagement, the outer shell is locked in a holding position.

5 Claims, 15 Drawing Figures PAIENTEDMIBZYW 3,881,982

cam 1m 5 FIG. 2

PAIENTEDmnzmu MU 20f 5 FIG. 3

FIG. 4

PATENTED 152N974 3.831 .982

SHEET 30f 5 FIG. 6

IOO

FIG. 7

I UNIVERSAL COUPLING BACKGROUND OF THE INVENTION:

a. Field of the Invention:

This invention relates generally to universal type couplings, and more particularly to a spherical coupling, one of the more well known types being a ball hitch used between a power vehicle and a trailer.

b. Statement of the Prior Art:

The prior art discloses several spherical couplings and trailer hitches that perform similar functions to some of the functions of this invention. But no known prior invention will perform the total function of the instant invention in the same manner using the same construction as herein disclosed and claimed.

Examples of such prior art devices may be seen in the following U.S. Patents:

No. Re. 24,362 to Nunn discloses a ball and socket hitch with an automatic safety latch that requires a pressing down movement to close and lock the connection. A pivoted semi-spherical wall engages the ball and is held there by spring pressure to absorb shocks and permit limited universal movement therebetween.

No. 2,833,564 to Brown is for a two part semispherical vehicle coupling housing that engages a ball hitch from above and is then locked in place. Approximately one-half of the split spherical housing is raised up to permit entrance of the ball and is then closed against the ball to hold it in place.

No. 3,374,268 to Groves is for a hitch construction wherein a ball joint upstands from a vehicle and is engaged by a trailer tongue having a downward opening socket. A locking sleeve surrounds the forward end of the trailer tongue and normally has a downward opening in registry with the socket opening. Once the ball is engaged, the sleeve rotates about the tongue axis and closes the bottom opening so the ball can not disengage. Only the upper half of the ball actually engages the socket to provide a seat that will remain in swivel contact with the ball as long as there is an uninterrupted downward force on the front end of the trailer tongue.

No. 2,848,253 to Walker discloses a hitch comprising a ball mounted on a towing vehicle and a socket formed as an extension at the front end of a trailer tongue. The socket has a downward facing opening and is installed vertically onto the ball, whereupon an internal receiving block, having a concave seat engaging the ball, is rotated 90 and moved forward to lock the ball and socket into a holding relation. The receiving block is moved by a crank handle that operates in a slot in the socket housing. When the installed position is reached, the handle is rotated to engage a lock nut on the bottom exterior of the socket housing until a detent on the top exterior of the socket is engaged.

While the prior art disclosures show several devices having useful purposes in the coupling art, none of them accomplish the Applicants purpose in the manner or with the structure of the Applicants invention.

SUMMARY OF THE INVENTION:

A principal object of this invention is to provide a universal coupling between two parts wherein the coupling comprises an upstanding spherical member and a socket member for horizontal alignment with the spherical member having a forward opening socket with an internal stationary cam that causes the members to engage in swivel fashion.

Another object of this invention is to provide a spherical coupling comprising a vehicle mounted ball and a trailer mounted socket wherein the engagement of the ball and socket may be accomplished by the vehicle driver without leaving the vehicle.

A further object is to provide a ball and socket hitch for a trailer-vehicle combination in which the trailer socket includes an opening facing and level with the vehicle ball so that the vehicle can be backed directly toward the trailer until the ball moves into engagement with the socket. After engagement and without any lifting or maneuvering actions the trailer socket may be locked into universal engagement with the vehicle ball. Thus no manual lifting or manuevering of the trailer tongue is required.

A still further object is to provide a universal coupling hitch wherein a housing on one member includes a handle that rotates first in a horizontal plane, and thence in a vertical plane, and then 90 in the horizontal plane again, when moving from a fully open to a fully closed and locked position of the hitch assembly. These maneuverings of the handle 19 in moving cylinder 12 from an opened to closed position serve a very useful purpose, in that the relatively long handle (needed for leverage purposes) is :moved thru its work cycle without colliding with the bumper or other parts of the vehicles as would occur in attempting to immediately rotate the handle between extreme positions. Another feature of this handle arrangement is that if it comes loose during travel it can only drop to the bumper and cannot accidently rotate to a point to expose and possibly permit the ball to escape from its socket.

BRIEF DESCRIPTION OF THE DRAWINGS:

FIG. 1 is a perspective view of one embodiment of the universal coupling of this invention showing the coupling members in a separated condition.

FIG. 2 is a cross-section elevational view of the coupling of this invention showing the members in an engaged condition.

FIG. 3 is a top plan view of the assembled members shown in FIG. 2.

FIG. 4 is a cross-sectional view taken along the lines 4--4 of FIG. 2 showing the double action cam of one embodiment.

FIG. 5 is a diagrammatic outline showing the relationship between the towing vehicle and the trailer when utilizing one of the features of the Applicants invention.

FIG. 6 is a view from the drivers seat of the vehicle of FIG. 5 showing how the vehicle and trailer may be aligned for automatic engagement. v

FIG. 7 is a cross-sectional detail elevational view of the socket housing of the coupling embodiment of FIG.

FIG. 8A is a layout plan view of a one-piece stamping to be used in forming an intermediate structure of FIG. 7

FIG. 10 is a side elevational view of another embodiment.

FIG. 11 is a detail elevational view, in cross-section of a means of mounting one spherical element of this coupling.

FIG. 12 is a side elevational view of a streamlined embodiment of the device of FIG. 1.

FIG. 13 is a front view of the socket of FIG. 12.

FIG. 14 is a cross-section taken at 1414 in FIG. 9.

DESCRIPTION OF ILLUSTRATED EMBODIMENTS:

This invention relates generally to universal or spherical couplings, but has as a specific embodiment the structure of a ball and socket hitch for attaching a power vehicle to a towed trailer for mutual transportation.

The embodiment generally indicated at l and shown in FIGS. 1 and subsequent is seen in FIG. 1 to comprise an upstanding ball unit 2 normally mounted on a towing vehicle 3, and a horizontally opening socket unit 4 normally mounted on a trailer tongue 5.

The ball unit or spherical member 2 comprises a ball or spherical element 6 supported by a pedestal or neck 7 a predetermined distance above the towing vehicle as indicated by its support structure 3. The vertical spacing of the ball and the vertical height of the socket unit 4 have a critical relationship for one operational mode of this invention, as will be more fully explained hereinafter. The pedestal may be attached to the ball and to the vehicle structure by any known method.

The socket unit 4 comprises a base plate 8 by which the unit 4 is attached to a trailer tongue structure as indicated at 5. This attachment may be made in any known manner, such as welding or by bolts (using bolt holes 9) or other fastening means. Stationary cam cylindrical socket l upstands from the forward end of base plate 8. A pair of pointed lugs 11 are attached at the extreme forward portion of plate 8 and are radially spaced from the stationary cylindrical socket 10. These lugs 11, not only guide the ball unit 2 into engagement with the socket 10, but also guide the rotary housing 12 in its operation to close open doorway 13 when housing 12 rotates in front of it. Cam cylinder includes an upstanding bearing disk 14 which cooperates with and guides rotary housing 12 in its horizontal rotation. The rearmost wall 15 of cylinder 10 is thicker than the remaining walls and thereby acts as a stationary cam when cylindrical housing 12 is rotated around cylinder 10. The cam action forces ball 6 into full seated engagement with the socket l6 defined by stationary cylinder 10. Thus the combination of the stationary cam cylinder 10 and the rotary door cylinder 12 forms a cam means to close the doorway 41 while simultaneously forcing the ball 6 into its proper seat 16 in socket unit 4.

The Webb 17 upstands from base plate 8 and is securely welded or otherwise attached thereto and to the top of disk 14 to stabilize the stationary cylinder 10. Rotary housing 12 includes a projecting boss 18 from which projects one end of handle 19. The opposite end of handle 19 includes a guard ring 20, beyond which the rod-like handle 19 is flattened and pierced to provide flat end 21 and locking hole 65. Opening 65 is adapted to receive a padlock when end 21 has projected completely thru opening 22.

When this invention has been installed on a vehicle and trailer as seen in FIG. 5, one unique feature of the invention becomes apparent. A person desiring to couple the ball hitch on the vehicle with the socket hitch on the trailer may now do so entirely from his drivers seat vantage point. The downward facing arrow 23b is attached to the houseboat or trailer T and downward facing arrow 23a is attached to the vehicle rear window by means of a decal transfer (not shown) at precisely the right location on the rear window to vertically align the ball hitch 2 on the vehicle V with the socket hitch 4 on the trailer T. When the vertical alignment is correct, the horizontal alignment is inherent, since the horizontal centerline C of the ball 6 substantially coincides with the horizontal centerline C of the socket portion of cylindrical socket 10. This horizontal alignment between hitch members 6 & 10 is accomplished by locating the ball hitch 2 on the automobile bumper or other structural member of the vehicle at a fixed height above the ground, and then locating the socket hitch 4 at the same effective height. If the normal installation of hitch 4 above the trailer frame is not correct for horizontal alignment, one manner of accomplishing this is seen in FIG. 7 wherein the socket is not installed above the trailer frame, but is installed at the desired height by offsetting frame 108. By this means the centerline C of the socket hitch 4 can actually be set where desired. For example, the frame of four-wheel houseboat trailer T of FIG. 5 would have a predetermined relationship to the height of the bumper of a specific vehicle so that the baseplate 108 may be offset the required amount during manufacture. If the trailer T is a two-wheel trailer, the flat baseplate 8 of the socket hitch of FIG. 1 may be used as the setting of the trailer jack to provide the desired height. Either of the above methods is effective in eliminating the requirement of the usual manual maneuvering of the trailer tongue in order to engage the members of a ball and socket hitch.

The socket hitch 104 of FIG. 7 is seen to include an offset baseplate 108, form the lower portion of which upstands a cylindrical socket 10 having a top boss 14 and a forward facing opening 41. Lugs lll surround each side of stationary socket l0 and are spaced therefrom to permit rotary housing 12 to rotate about the socket walls and boss 14 in guided relation. Since the socket 10 is in effect a stationary cam, the ball 6 will be securely seated into socket recess or cavity by the rotation of rotary housing 12, which acts as a cam follower. Once seated, the ball 6 and the complete socket of recess 100 and the inner wall of housing 12 and the bottom support plate bevel 142' firmly enclose and support the ball member 2, and yet permit easy swivelling between the ball and socket members over a wide range of movement. Upon completion of the engagement operation, handle 19 of socket hitch 104 is engaged into hole 122 in the manner described relative to FIG. 1. A grease fitting G (FIG. 3) is optional and installed after drilling a small hole thru cap 14.

The double cam action shown in FIG. 4 is an alternate method of engagement, altho a cam on only one stationary cam cylinder (such as 10) is satisfactory in many instances. FIG. 4 also shows the means for connecting handle 19 in boss 18 for rotary action. The end of handle 19 residing inside boss 18 includes a groove 30 which is intercepted by a rollpin 31 that projects into a thru hole 32 in the boss. Near the other end of handle 19, the rigidly attached washer 20 plays an important role of abutting webb 17 and thereby positively positioning the forward facing opening in rotary carn follower cylinder 12 and rotary cam cylinder 12'.

FIGS. 7-10 show modified embodiments of this invention and particularly structure which is adaptable to very economical construction and assembly method that would lend itself to mass production operations. The structure of FIGS. 8 and 9 may be employed in manufacturing either of the embodiments of FIGS. 7 or 10.

FIG. 8A shows a one-piece stamping of part 108 with bolt holes 109 and locking holes 222 all punched in place. In another operation to flaps 220 are also pierced and the sides 108B are folded down along lines F and F while frontal flap 108C is folded twice along lines F 3 & F 4 into an L-shaped arm to provide a forward extending bottom plate 140. Lugs 111 are simultaneously curved to surround bottom plate 140. These lugs lend additional support against the forward pull of the vehicle and also may be used (FIG. 4) as an auxiliary cam guide. The piece 108 thus formed is seen in FIGS. 7 & 9. The forward facing slot 141 in bottom plate 140 is beveled at 142 completely around the slot opening on the bottom side. Similarly, auxiliary plate 140' includes a top side bevel 142 so that when plate 140' overlies plate 140 and the slots 141 and 141' are in registry, the ball 6 will be snugly supported within the socket housing cavity and the neck 7 will have ample clearance relative to plate 140 to permit substantial swivel action; namely, the maximum swivel action likely to be encountered between a pulling vehicle and its trailer. This may be seen in FIG. 11 and represents an important feature of providing a completely enclosed cavity that contains the ball 6 while providing rugged and sturdy bottom, side and top support, which will permit the substantial swivel action both in a horizontal and vertical direction without permitting any vertical linear play of the ball in its cavity 116. Prior art hitches have been generally deficient in this vertical swivel and many have broken when subjected to not uncommon vertical forces.

FIGS. 9 8t 10 show a modified embodiment of the device of FIG. 7. In this embodiment, the piece 208 is substantially the same as piece 108, except that surrounding its slot 241 (corresponding to 141 of FIG. 8A) the metal is upset to form a reinforcing ridge 250. Bevels 242 are formed when member 240 is upset to form ridge 250 as shown in FIG. 14 as an alternate to a flat upset. This ridge 250 makes it unnecessary to utilize auxiliary piece 140 and yet provides effective support and a bearing surface for the bottom rotating edge of rotary cup 10. Bolts 251 extend thru the trailer tongue T and secure the socket hitch 201 to the tongue by means of nuts 252. In this embodiment, the top holes 209 support upstanding studs 210 which are welded at the underside to plate 208A, or fastened by any suitable means.

The finished structure identified at 201 in FIG. 10 is shown in its closed and locked position about ball 6 (not shown), which is supported from vehicle structure 3 by neck 7. Once the formed structure 208 is completed, the cylindrical socket structure 10' including the stationary cam structure 15 is welded onto platform 250 in such a manner as to leave room for rotary cylinder 12 to revolve around the periphery of cylinder 10 and remain on platform 250. Cylinder structure 10 including a higher top boss 214 (than boss 14 of FIG. 1)

is supported in part by top cover plate 261. This higher boss 214 projects into or thru an opening 260 in cover plate 261 to which it may be secured by welding if desired. If it is not welded, the rotary cup 12 could be easily replaced in the field if necessary. Cover plate 261 overlys top plate section 208A and includes openings 262 which register with studs 210 so that nuts 263 may engage studs 210 and secure the plate 261 to the 208A structure to form the socket hitch assembly 201.

The handle 219 is pivoted in boss 18 and in the same manner as in FIG. 1 it acts as a lever to force ball 6 into socket 10 by moving to its locked position as shown in FIG. 10. Side plate 2088 includes flap 220 which is bent outward so that its opening 222 may receive the formed handle end 264 with its lock receiving hole 265.

FIGS. 12 & 13 illustrate another embodiment of the device of this invention. In this embodiment, identified generally at 301, the socket hitch structure 304 is adapted to utilize rugged formed structural spherical shaped rotary and stationary socket parts. While many socket hitches marketed today use housings shaped to conform with the ball hitch member, they are largely made of sheet metal and are intended to be selfsupporting. However, it has been found in actual practice that the pulling or resistive load on the sheet metal housing can rupture the housing in certain angles of pull encountered by the towing vehicle. When the relatively thin sheet metal enclosure breaks, the hitch must be replaced since it is then no longer safe for road travel. In the present arrangement, the structural ball receiving socket member and ball enclosing door member both conform generally to the shape of the contained ball, but neither are made of sheet metal, but rather of steel castings or forgings, and the ball retaining members are additionally supported by Webb 317, so that all forces normally encountered in towing operations are safely met, and contained by the structure and bracing arrangement disclosed. The entrance lugs 311 include a tapered guiding entrance bevel 311A, as do cylindrical door 312 and stationary cam socket 310 (bevels shown at 312A & 310A). The bottom plate 340 includes ball support surfaces 342 and clearance surface 342 at entrance opening 341 and thruout the cavity.

It should be noted that in the foregoing construction no threaded connections are employed in the area of the ball or socket, since threads are inherently weaker than equipment unthreaded parts, and particularly in the field of vehicle hitching, this weakness gives rise to breakage. Also contributing to the strength factor is the applicants arrangement whereby the pulling force is substantially all resisted by the stationary (welded on) cylinder & lugs rather than by the rotary cylinder alone.

From the foregoing description and examples, it will be seen that there has been produced a device which substantially fulfills the objects of this invention as set forth herein. The invention is not limited to the exemplary construction herein shown and described, but may be made in many ways within the scope of the appended claims.

We claim:

1. A universal connection between at least two separate parts, comprising:

a. a spherical member attached to one part,

b. a spherical element in said spherical member,

c. a neck in said spherical member connecting said spherical element and said spherical member to said one part,

d. a housing member attached to the other part,

e. said housing defining an initially open forward facing front door,

said door opening having one size corresponding to said spherical element and another size corresponding to said neck for allowing swivel movement in all directions of said housing member about said spherical element,

g. means to horizontally align said element and neck with corresponding sizes in the door opening whereby relative linear movement of said members will permit engagement thereof,

h. and cam follower means to close said door opening and lock said spherical element in said housing member against unintentioanl disengagement,

. wherein said housing includes a stationary cam cylinder defining a sphere receiving cavity and said door opening,

j. and wherein said cam follower comprises a rotary cam follower cylinder surrounding said stationary cam cylinder.

2. A universal connection as in claim 1, wherein said stationary cam cylinder forms a stationary cam about which the rotary cam follower cylinder rotates in such a manner as to forceably pull said spherical member into and securely seat said spherical element within said sphere receiving cavity, which cavity when cooperating with said rotary cam follower cylinder forms a substantially complete circular cross section.

3. A universal connection as in claim 1, wherein said cam follower means includes a handle and said housing member includes means for locking said handle in at least one position of said cam follower means.

4. A universal connection as in claim 3, wherein said housing member includes means for locking said handle in both the fully opened and fully closed positions of said cam follower means relative to said door opening.

5. A universal connection comprising:

a. a ball hitch structure having a ball member mounted on a vehicle,

b. a socket hitch structure mounted on a second vehicle,

c. said socket hitch structure having a generally spherical stationary concave socket member having a cavity and an opening thereto facing said ball member in horizontal alignment therewith,

d. spherically contoured door member surrounding said socket member and adapted to close said cavity and form a substantially circular cross section configuration when said ball member is therein,

e. at least one of said members acting as a cam to direct said ball member into seating engagement with said socket member,

f. and leverage means to rotate said door member with the force required by said member acting as a cam to move said socket hitch and said second vehicle as required to provide a universal connection between said ball hitch structure and said socket hitch structure. 

1. A universal connection between at least two separate parts, comprising: a. a spherical member attached to one part, b. a spherical element in said spherical member, c. a neck in said spherical member connecting said spherical element and said spherical member to said one part, d. a housing member attached to the other part, e. said housing defining an initially open forward facing front door, f. said door opening having one size corresponding to said spherical element and another size corresponding to said neck for allowing swivel movement in all directions of said housing member about said spherical element, g. means to horizontally align said element and neck with corresponding sizes in the door opening whereby relative linear movement of said members will permit engagement thereof, h. and cam follower means to close said door opening and lock said spherical element in said housing member against unintentioanl disengagement, i. wherein said housing includes a stationary cam cylinder defining a sphere receiving cavity and said door opening, j. and wherein said cam follower comprises a rotary cam follower cylinder surrounding said stationary cam cylinder.
 2. A universal connection as in claim 1, wherein said stationary cam cylinder forms a stationary cam about which the rotary cam follower cylinder rotates in such a manner as to forceably pull said spherical member into and securely seat said spherical element within said sphere receiving cavity, which cavity when cooperating with said rotary cam follower cylinder forms a substantially complete circular cross section.
 3. A universal connection as in claim 1, wherein said cam follower means includes a handle and said housing member includes means for locking said handle in at least one position of said cam follower means.
 4. A universal connection as in claim 3, wherein said housing member includes means for locking said handle in both the fully opened and fully closed positions of said cam follower means relative to said door opening.
 5. A universal connection comprising: a. a ball hitch structure having a ball member mounted on a vehicle, b. a socket hitch structure mounted on a second vehicle, c. said socket hitch structure having a generally spherical stationary concave socket member having a cavity and an opening thereto facing said ball member in horizontal alignment therewith, d. spherically contoured door member surrounding said socket member and adapted to close said cavity and form a substantially circular cross section configuration when said ball member is therein, e. at least one of said members acting as a cam to direct said ball member into seating engagement with said socket member, f. and leverage means to rotate said door member with the force required by said member acting as a cam to move said socket hitch and said second vehicle as required to provide a universal connection between said ball hitch structure and said socket hitch structure. 